Electromagnetic device, more particularly for use with contactors, relays and telebreakers



Se t. 13, 1966 P. FRANCK 3, 72,940

ELECTROMAGNETIC DEVICE, MORE PARTICULARLY FOR USE WITH CONTACTORS. RELAYS AND TELEBREAKERS Filed March 31, 1964 2 Sheets-Sheet 1 ,3 6 U INVENT R PIERRE FRANCK ATTORNEYS p 13, 19% P. FRANCK 3,272,940

ELECTROMAGNETIC DEVICE, MQRE PARTICULARLY FOR USE WITH RELAYS AND TELEBREAKERS CONTACTORS,

2 Sheets-Sheet 2 Filed March 51, 1964 INVENTOR PIERRE FRANCK H ATTORN Y5 United States Patent 3,272,940 ELECTROMAGNETIC DEVICE, MORE PARTICU- LARLY FOR USE WITH CONTACTORS, RELAYS AND TELEBREAKERS Pierre Franck, 53 Ave. de Trudaine, Paris, France Filed Mar. 31, 1964, Ser. No. 356,236 Claims priority, application France, June 19, 1963, 938,636 9 Claims. (Cl. 335-122) This invention relates to an electromagnetic actuating device, more particularly for use with electromagnetically actuated switch contactors, relays and telebreakers or remote control switches, and its aim is to permit the construction of particularly compact units.

An electromagnetic switch actuating device according to this invention is characterized by a coil of the solenoid type having mounted thereon two diametrically opposed pole-pieces, and by a mobile assembly comprising an axial plunger core and a transverse adjustable vane-like armature member, which assembly is mounted on the coil in such manner as to move, in response to the combined forces due to the mechanical ifOI'CS of the system and to the magnetic field of the coil, with a helical motion compounded of a translation along the coil axis and a rotation thereabout. The electromagnetic actuating device of this invention is well-suited in particular to control a rotating drum made of insulating material and operating after the manner of a cam up on the travelling blade arm of a switch, whereby to open or close the switch.

It has been found that it is preferable, in order to ensure efficient operation of this electromagnetic device, to use the linear translation or working component of this helical motion for obtaining the pressure force acting on the switch blade contacts, this translation or working component producing rotation of the drum made of insulating material, while the rotational component of the helical motion is utilized for release and return motion tothe rest position of said mobile assembly including the plunger core of the electromagnetic actuating device.

In this Way, this helical motion is utilized to operate the various mechanisms and permit design simplifications as compared to the prior art devices using simple translational motion (plunger cores) or partial rotation (coils with a rotating armature), since a single member possessed of a composite helical motion is capable of fulfilling dual functions (pressure and release forces), whereas two single-motion members would otherwise be required to fulfill these two functions.

A further feature to be observed is that the rotating drum made of insulating material is mounted with its axis perpendicular to the coil axis and is provided with flutings engageable by a cam-shaped control member adapted to thereby rotate the rotating drum and which may be rigidly connected to the coil shaft when desired.

Still another feature relates to this cam-shaped control actuating member, which is separable from the coil shaft but can be rigidly united therewith through quickattachment means when desired, as by electric arms. The configuration of said cam-shaped actuating member is such that the latter possesses two different partial profiles, one profile of which permits operation as a step-by-step relay or as a remote control switch or telebreaker, and the other partial profile permits operation as an on-off relay, either of these operating modes being selected by 3,272,940 Patented Sept. 13, 1966 merely manually turning around and adjusting the drum actuating control member.

In the telebreaker or step-by-step relay functional mode of operation, said actuating control member is in engagement with the drum fluting, and the translation component of the helical motion causes said control memher to rise and thereby engage and rotate the drum in one direction. By reason of the form of construction of the unit assembly and more specifically because of the relative positions of the drum actuating member and the drum, this actuating control member rotates slightly at the end of the translational working phase and starts to move on the rotation component of the helical motion which, as it takes place, disengages said drum actuating control member from the drum fluting and enables the electromagnetic actuating device assembly to revert to the rest position after the coil has been de-energized, without causing the drum to be rotated backwards again.

On the other hand, in the on-01f relay functional mode of operation, the partial profile of the drum actuating control cam member is such that the latter invariably remains engaged with the same drum fluting, during both the working phase and the return phase to the rest or break position, the drum being in this case driven alternately forward and backwards.

In addition, the rotating drum has mounted thereon control members for controlling the switch contacts, and such control members can be polygonal prism-shaped plates and have projecting portions such as projecting edges for closing the switch contacts and recessed portions such as prism-shaped fiat faces for opening the contacts.

In the preferred form of embodiment, at least one of said contact control members is adjustable, i.e. can be shifted radially angularly about the axis with respect to the other contact control members whereby to provide, with a single unit, relays or electromagnetic switches having a variable number of making and rest or break contacts.

The description which follows with reference to the accompanying non-limitative drawings of examples will give a clear understanding of how the invention can be carried into effect and will disclose yet further features and advantages thereof.

In the accompanying drawings:

FIGURE 1 is a front view of a first form of embodiment of the invention wherein the electromagnetic actuating device is designed for a three-pole switch unit.

FIGURE '2 is a section taken through the line IIII of FIGURE 1.

FIGURE 3 is a section taken through the line IIIIII of FIGURE 1.

FIGURE 4 shows in perspective on an enlarged scale the electromagnetic actuating device of the form of FIG. 1 in particular.

FIGURE 5 shows on an enlarged scale the cam-shaped reversible control member for transmitting the motion of the electromagnetic actuating device to the movable mechanical components of the unit of FIG. 1.

FIGURES -6 and 7 respectively shown the cam-shaped reversible control member in an operative position for operation as an on-oft" type relay and in an operative position for operation as a telebreaker or a step-by-step relay.

FIGURE 8 is a front View, with fr-agmental section, of a second modified, simplified, small form of embodiment of the invention wherein the electromagnetic device is adapted for use on a single-pole unit, and

FIGURE 9 is a side elevation view corresponding to FIGURE 8.

Reference is first made to the embodiment of FIG- URES 1, 2 and 3, whereon reference numeral 1 designates a base made of insulating material onto which is mounted an electromagnetic actuating device general-1y designated by numeral 2 and having two pole-pieces 3 forming an inverted U secured fixedly to the base 1. The lower ends of pole-pieces 3 embody convex portions 4 facing radially inwardly into the channel section or U formed by the pole-pieces 3. Between the pole-pieces is positioned a solenoid coil 5 of conventional type through which extends a vertical shaft 6 adapted to slide and rotate in brackets 7 at its upper and lower extremities. A stationary core 8 fixedly attached to coil 5 and pole-pieces 3 is mounted within coil 5 and has an axial bore and surrounds shaft 6 but allows shaft 6 to move within stationary core 8.

The lower part of shaft 6, between coil 5 and the lower bracket 7, is fixedly attached by a movable plunger core 9 to which is adjustably fixed a transverse radially mounted adjustably vane-like plate armature member 10. Each end of armature member 10 embodies a concavity recess 11 shaped to substantially match the convexity 4 on the ends of the pole-pieces 3. The purpose of concavity 11 in armature member 10, in combination with the convexity of portions of pole pieces 3, is to have a larger air gap in the normal position, this gap becoming small only at the end of the rotating movement of armature member 10. It is necessary that armature member 10 be not attracted by the pole pieces 3 before having made its upwards movement.

The lower bracket 7, is provided with a bearing abutment 12 adapted to limit axial movemental of transverse armature member 10 and hence also vertical shaft 6 when the coil is de-energized.

The shaft 6 extends upwardly beyond pole-pieces 3 and supports on this upper portion-in longitudinally axially fixed relation but rotatable, a cam-shaped reversible selecting control member 13 extending perpendicularly to said shaft and may be rigidly attached thereon. Camshaped member 13 can be manual-1y adjustably rotated around shaft 6 into either one of two positions, but is not longitudinally displaceable along shaft 6. Between member 13 and upper bracket 7 the shaft is surrounded by a return spring 14 which urges shaft 6 and vane armature plate 10 into its normal rest position shown on the drawing.

The cam-shaped reversible control member 13 is rotatable on shaft 6, and, in order to enable it to be replaced with certainty in an appropriate desired position, is inserted within a housing formed by two half-shells 15 which are fixedly attached to shaft 6 and leave between them a gap substantially equal to the thickness of control member 13.

As is clearly shown in FIGURE 5 in particular, the two half-shells15 are interconnected by a connecting block 16 of reduced rectangular section rigid with shaft 6. The control member 13 is readily fitted onto connecting-block 16 and embodies to that end a rectangular cut-out 17 matching the section of connecting-block 16. Said cut-out 17 opens outwardly via a neck 18 of smaller width than the width of section 16, and said neck is formed between two elastic clamping arms 19 and 20 which spread apart when the member 13 is fitted over the connecting-block 16 of half-shell 15 through the neck 18 and which then, due to their elasticity, revert to their original position of FIGURE 5 in order to securely clamp the connecting-block 16. Half-shells 15 and connecting block 16 are permanently fixedly secured to shaft 6.

The control member 13 has a first convex edge or peripheral part 21 (FIG. 5) which permits operation as an on-off relay and also has another slightly convex edge or peripheral part 22 extended by a rectangular stub portion 23, for operation alternatively as a step-by-step relay. In order to obtain either of these functional modes of operation, the control member 13 actuates a horizontal cylindrical drum 25 adapted to rotate about a stationary shaft 26 supported in retaining bosses 27 fixed to the base I. Said drum 25 is preferably made of plastic and embodies over a portion of its periphery flutings 28 of suitable depth into which engage either the edge 21 or the rectangular projection 23 of control member 13 as set, according as operation is desired as an on-oif relay or as to step-by-step relay. For changing the mode of operation of actuating control cam member 13, member 13 is released elastically from the shaft 6, to return it in such a manner that its previously upper face becomes the lower face and to replace it elastically in position between the shells 15 in such a manner that the arms 18-19 clamp again the connecting block 16 (see FIGS. 6 and 7).

Drum 25 carries a terminal cogged ring 29 engageable with a fixed locking catch or dog or latch 30 fixed to the base 1, which catch permits, in a manner well-known per se, rotation of the drum in one direction only for operation as a step-by-step relay. This catch 30 can be Withdrawn from operation when it is desired to operate as an on-off relay. Drum 25 further comprises a set of polygonal prism-shaped plate members 31 of which the peripheral faces 32 are substantially tangential to the extended cylindrical surface of the drum and of which the apexes 33 form projections. In the example shown in the drawing, said prism-shaped members are hexagons but it will of course be understood that pentagons octagons, etc., could be provided in lieu thereof to suit requirements. It is to be noted that the number of polygonal prism-shaped members can vary with the number of switch contacts to be actuated and that one or more polygonal prism-shaped members may be slipped tightly lockingly over or fitted to, instead of being molded integrally with, the unfluted portion of the periphery of the drum 25. Thus, in the specific example of FIGURE 1, the right-hand polygonal prism-shaped member denoted by reference numeral 34 is such a separate fitted member and is rotatable about the drum shaft 26 into either of two positions, to wit, -a position shown in FIG- URE 1 similar to the positions of the polyganol prismshaped members 31 which are fixed relative to the drum, or a position angularly offset by /n in the case of a polygonal prism-shaped member of n sides. In the example shown, hexagon prism-shaped member 34 would be offset by 30 relative to the stationary prism-shaped members 31. Thus, in the first position of polygonal prism-shaped member 34, i.e. the position shown in FIG- URE 1, the three polygonal prism-shaped members operate the three switch contacts 36 in the same sense, whereas in the second offset position of polygonal prismshaped member 34, a relay or electromagnetic switch will be provided having two make or closed circuit contacts and one rest or break or open circuit contact for example, or, conversely two rest or break or open circuit contacts and one make or closed circuit contact.

In this way, using a single unit and operating only on the polygonal prism-shaped members attached to the drum, i.e. without touching the switch contact elements, which can be adjusted once and for all, it is possible to obtain three operative contacts, or two make or closed circuit contacts and one rest or break or open circuit contact, or two rest contacts and one make or closed circuit contact, or three rest or break or open circuit contacts.

The switch contacts 36 consist, in the manner well known per se, of a movable contact on a travelling blade arm 37 which is connected at one end to a current output terminal 39 secured to base 1 and which arm 37 rides.

over a hexagonal prism-shaped member attached to drum 25 whereby to be actuated by the same, and further consists of a fixed contact on a stationary arm 38 fixed to the base and having one end connected to a current input terminal 40.

Reference numeral 41 designates the current input and output terminals for energizing the solenoid coil 5 of the electromagnetic actuating device.

Broadly, operation of a telebreaker or remote control switch according to this invention is as explained hereinbelow. When the solenoid coil 5 is energized, the flux of the magnetic field which is produced follows a path that passes through the plunger core 9, the stationary core 8, the pole-piece 3 and the armature member 10.

The plunger core 9 is attracted by the stationary core 8, and the armature member fixed thereto tends to move upwardly in vertical translation as does also shaft 6 fixedly attached to plunger core 9. For as will be particularly clear from FIGURE 4, when the coil is deenergized, .the armature member 10 makes a large angle ,8 with the centerplane of the pole-pieces 3, so that the air-gap between the armature member 10 and the inner surface 4 of the pole-pieces is sufliciently large for the electromagnetic force tending to rotate the armature member 10 about its axis not to have any effect. The electromagnetic force tending to rotate armature member 10 is the attraction exerted by the pole pieces 3 on the armature member 10 like the attraction of a magnet which has an effect only at a small distance. The electromagnetic force tending to impart a vertical translational motion to plunger core 9 being adequate, the armature member 10 is moved upwardly and carries with it shaft 6 and the cam-shaped control member 13 which, irrespective of its radial position on to shaft 6, is engaged by one of its peripheral edges or faces 21 or 23, in a fluting 28 of drum 25. When shaft 6 and armature member 10 are thus in their upper positions, in one of its radial positions on shaft 6, cam-shaped member 13 has its edge 21 engaged in a fluting, and in its other radial position, camshaped member 13 has its rectangular stub portion 23 engaged in a fluting. These positions correspond respectively, to operation as a step-by-step relay, and as an on-otf relay.

The control member 13 consequently rotates drum 25 through an angle at (see FIGURE 3), and the prismshaped members 31 and 34 attached to the drum close or open the switch contacts 36 according as the travelling contact arms 37 engage the apexes or flats of said prismshaped members. The upper face of cam member 13 in the position of FIG. 6 becomes the lower face in the position of FIG. 7. In both cases the cam is secured to shaft 6 by the elasticity of its arms 19-20 which clamp the connecting block 16, the latter being permanently secured to shaft 6.

As shown in FIGURE 3, the cam-shaped control member 13 engages when at rest with a drum fluting 23 located below the drum shaft and moves, when operated to approximately the same level as said drum shaft. As the drum 25 rotates, the cosine of radial angle a (FIG. 3) continues to increase; in other words, the distance, as projected on the horizontal plane through the drum shaft 26, between the drum shaft and the extreme tip of the control member 13 engaged fully home into the fluting, increases shaft 6 can in general move linearly along in its longitudinal axis and rotate about that axis. Since the horizontal shaft of drum 25 and the axis of the vertical shaft 6 at this instant are stationary, the control member 13 is constrained to rotate in the horizontal plane by reason of the fact that the point of contact of control member 13 with the bottom of the fluting 28 is, as projected horizontally, sutficiently distant from shaft 6 to prevent jamming. When the coil 5 is energized, stationary core 8 and pole pieces 3 are energized and the plunger core 9 is attracted upwards by the stationary core 8 and armature 10 and the control member 13 raise the fluting 28 towards the horizontal diametral plane of the drum 25. Thus the fluting 28 comes nearer to shaft 6 and causes a partial rotation of shaft 6 by pushing against control member 13. Thus, rotation of the drum through an angle at (FIG. 3) partially rotates the control member 13 and the shaft 6 with which it is rigid, together with the vane 10, the effect of this partial rotation being to reduce the angle ,8 between the vane armature 10 and the pole pieces (FIG. 6) to a value such that the air-gap between the vane 10 and the pole-pieces 3 is reduced and consequently enables the electromagnetic force to operate and complete the revolution of the transverse vane armature member 10 to cancel out the angle [3. The B-rotation is thus initiated by the action of a force which results from the translation of plunger core 9 and the mechanical forces of the device. This fl-rotation is then completed by an electromagnetic force acting on the armature member 10.

The initial rotation of cam member 13 is due to the fact that the fluting in which it is engaged comes nearer to shaft 6 when this fluting moves upwards as far as the horizontal diametral plane of the drum 25. Vertical shaft 6 can rotate about its axis and can move longitudinally in its axial direction, but its axis remains unchanged in the same position. The continuation of the rotation of cam member 13 is due to the decreases of the air-gap between armature member 10 and pole pieces 3 as has been explained above. The magnetic force cancelling out the angle [3 is the attraction exerted by the pole pieces 3 on the armature member 10 when this armature member has already made an initital rotation which sufficiently decreases the gap between the pole pieces 3 and the armature member 10.

When the device is operating as a telebreaker or stepby-step relay or remote control switch, i.e. when the cam-shaped control member 13 is manually placed in the position of FIGURE 7 with the rectangular stub 23 engaging a drum fluting 28, the rotation of the vane armature 10 and cancellation of angle [3 rotate the control member 13 until it assumes the position shown in broken lines on FIGURE 7, wherein the rectangular extension 23 disengages completely from the fluting of drum 25. The cam-shaped member 13 is placed in the position of FIG. 7 by a manual adjustment when it is desired to have an operation in which the drum 25 does not return to its original position when the coil 25 is de-energized. The device may thus operate in two different manners according to the position manually given to cam 13. As long as the position of cam member 13 is not manually changed, the operation remains the same. When coil 5 is de-energized, the return spring 14, which had been compressed by the vertical translation of shaft 6, restores the stored energy and causes the control member 13 and the armature member 10 to descend anew to their rest position by imparting to these components a reverse helical motion to that which they sustained during the initial operative phase of the movement. Thus, on being disengaged from drum 25, the control member 13 will translate vertically, and simultaneously rotate in order that the rectangular extension 23 can engage with the next drum fluting; during this return motion to the rest position, however, the fixed catch 30 will immobilize the drum. The helical movement of the assembly of the plunger core 9 and the vane armature member 10 has a first cause which is the vertical attraction of the plunger core 9 combined with the rotation of drum 25. When plunger core 9 moves upwardly, cam member 13 causes drum 25 to rotate and the fluting in which cam member 13 is engaged comes nearer to shaft 6. When the fluting 28 rotates about the horizontal axis of drum 25, it necessarily moves in a vertical direction and also in a horizontal direction, the cam member 13 being initially below the axis of drum 25. The second cause of the helical movement is the attraction of the armature member 10 by pole pieces 3. This second cause has for effect to complete the rotation movement of cam member 13 The rotation of cam member 13 is made at the same time as the translation under the action of the return spring which exerts a downward force as well as a torque due to the torsion applied on it by the previous upward helical movement.

When the device operates as an on-olf relay, i.e. when the cam-shaped control member 13 is placed in the position of FIGURE 6, the cam-shaped control member 13 is adjusted so that the convex partial profile 21 of said control member remains engaged with the same fluting of drum 25, both during its upward operative movement and its downward rest return movement. As FIGURE 6 clearly shows, when control member 13 is moved upwardly by upward displacement of shaft 6 and rotates the drum 25 forward, it undergoes a rotation resulting from cancellation of the angle between the vane armature and the pole-pieces 3 that brings control member 13 into the position shown in broken lines.

In this position, the convex partial profile 21 of control member 13 remains engaged in the same fluting. When coil 5 is de-energized, the control member 13 will descend anew in response to return spring 14, and in so doing will rotatably drive the drum 25. In this mode of operation as an on-off relay, the fixed catch 30 must be eliminated in order to permit return rotation of drum 25.

It will be manifest that if the cam-shaped control member 13 is engaged in a drum fluting in such manner that in moving from the resting position to the operative position it produces closure of the switch contacts 37 through the action of the polygonal prism-shaped members attached to drum 25, opening of said contacts will be obtained if the control member 13 is engaged in a fluting immediately adjacent the aforementioned fluting.

Shown in FIGURES 8 and 9 of the accompanying drawing is a modified form of a small single-pole telebreaker or remote control switch of particularly simple design specifically intended for mass production. The operating principle of this little unit is identical to that hereinbefore disclosed.

In FIGS. 8 and 9 mounted on a base 51 is an electromagnetic actuating device 52 consisting of stationary polepieces 53 and a coil 54 having extending therethrough a vertical shaft 55 supporting a plunger core 56 carrying at its lower end a transverse armature member 57. The movable shaft 55 carries at its upper end a cam-shaped part 58 lodges beneath one of the cogs 59 of a ratchet- FIG. 1 and which is fitted over said moving shaft 55.

As an alternative embodiment, the cam-shaped part 58 may be molded in plastic, and the shaft 55 driven as a tight fit into the core 56. In the unactuated position of this electromagnetic actuating device, the cam-shaped part 58 lodges beneath one of the cogs 59 at a ratchetwheel 60 forming part of a drum assembly 61 having a horizontal shaft 62 and comprising a polygonal prismshaped member 63 cooperating with the travelling blade arm 64 of a switch contact which is fixed to a terminal 65 and faces a fixed contact stud 66 integral with a terminal 67. Numerals 69 and 70 designate the current input and output terminals for energizing the solenoid coil 54.

The manner of operation of this single-pole telebreaker or remote control switch of the modified form of FIG 8 is simple to understand: when the coil 54 is energized it pulls in the core 56, which translates vertically upwards. The cam-shaped member 58 rises and rotates the drum 61 by acting on the cog 59 of ratchet-wheel 60 with which it is in mesh. In the upper position of member 58, the polygonal prism-shaped member 63 drum 61 closes the switch contact 64-66 for example, since the travelling blade switch arm 64 of that contact is then riding over an apex of the polygonal prism-shaped member.

, The transverse armature member 57 then rotates to reduce the air-gap between itself and the pole-pieces 53, thereby enabling the cam-shaped member 58 to fully disengage from the ratchet-wheel teeth 59. When the coil is de-energized, the moving assembly consisting of the plunger core 56, the armature member 57, the shaft 55 and the cam-shaped member 58, returns to the rest position shown in the drawing, and the cam-shaped member 58 then moves into a position beneath another tooth of the ratchet-wheel. Provision may be made for a return spring (not shown) in order to facilitate the return of the moving assembly into the rest position.

While there has been shown and described, the presently preferred embodiment of the electromagnetic device of this invention, it will be well understood by those skilled in the art that various changes and modifications may be made in these embodiments. It is, therefore, to be understood that the description hereinbefore set forth is not to be considered a limitation of the invention, but that changes may be made within the spirit and scope of the invention as set forth in the appended claims.

I claim:

1. An electromagnetic device for rotating intermittently a mechanical member comprising in combination a solenoid type coil having a vertical axis, two pole-pieces arranged in diametrically opposed adjacent positions with respect to said coil, a movable assembly having a vertical shaft extending beyond said coil, a plunger core connected with said shaft adapted to move axially androtatably within said coil, and a transverse armature member carried at one end of said core, a mechanical drum member rotatable about an axis perpendicular to said shaft and having flutings on a cylindrical portion thereof, an operating fiat member carried by said shaft and shaped for engaging at least one of said flutings in a position spaced from the axis of said mechanical member, means for energizing said coil and causing an axial movement of said plunger core and shaft thus moving axially said operating member towards the horizontal diametral plane of said mechanical member, whereby the relative movement of said fluting with respect to said shaft causes the initial rotation of said shaft by a pushing action of said fluting against said operating member in a direction which reduces the angular gap between said armature and said pole pieces, thus permitting the electromagnetic flux between the pole pieces and the armature to complete a rotation movement of said shaft. 7

2. In an electromagnetic switch operating mechanism, a solenoid, pole pieces mounted adjacent said solenoid, a plunger core mounted axially displaceably within said solenoid, a shaft attached to said plunger core and extending axially through and beyond the ends of said solenoid, an adjustable cam member carried on said shaft and displaceable with axial movements of said shaft, a fluted drum mounted adjacent said cam member and with the axis of said drum extending substantially perpendicular to said shaft, said drum having peripheral flutings positively engageable with said cam member, an armature plate displaceably mounted on said plunger core, spring means mounted for returning said shaft and said plunger core to normal position when said solenoid is de-energized, a controlled member, and cam means mounted on said drum and adapted to engage and displace said controlled member.

3. A mechanism according to claim 2, said cam means being polygonal prismatic plates.

' 4. A mechanism according to claim 2, said cam means being polygonal prismatic plates, and at least one of said polygonal plates being displaceably adjustably mounted on said drum.

5. A mechanism according to claim 2, and a cogged ring mounted on said drum, and an adjustable locking catch mounted engageably with said cogged ring and adapted when actuated to permit rotation of said drum in only one direction.

6. A mechanism according to claim 2, the periphery of said cam member having a first portion which is a convex arc and having a second portion which is a rectangular stub and being selectively adjustable to place either of said portions into actuating position.

7. A mechanism according to claim 6, and a connecting block fixedly mounted on said shaft, and said c-am member being fitted on to said connecting block.

8. A mechanism according to claim 7, and two shielding half shells fixedly mounted on said shaft and being interconnected by said connecting block and being adapted to receive between them said cam member.

9. A mechanism according to claim 2, said cam member being mounted on said shaft rotatably about the 10 longitudinal axis of said shaft, but fixed on said shaft as to longitudinal movement along the axis of said shaft.

References Cited by the Examiner UNITED STATES PATENTS 4/1951 Brockway 200-105 2/1959 Buchtenkirch 317-192 X BERNARD A. GILHEANY, Primary Examiner. I. J. BAKER, Assistant Examiner. 

1. AN ELECTROMAGNETIC DEVICE FOR ROTATING INTERMITTENTLY A MECHANICAL MEMBER COMPRISING IN COMBINATION A SOLENOID TYPE OIL HAVING A VERTICAL AXIS, TWO POLE-PIECES ARRANGED IN DIAMETRICALLY OPPOSED ADJACENT POSITIONS WITH RESPECT TO SAID COIL, A MOVABLE ASSEMBLY HAVING A VERTICAL SHAFT EXTENDING BEYOND SAID COIL, A PLUNGER CORE CONNECTED WITH SAID SHAFT ADAPTED TO MOVE AXIALLY AND ROTATABLY WITHIN SAID COIL, AND A TRANSVERSE ARMATURE MEMBER CARRIED AT ONE END OF SAID CORE, A MECHANICAL DRUM MEMBER ROTATABLE ABOUT AN AXIS PERPENDICULAR TO SAID SHAFT AND HAVING FLUTINGS ON A CYLINDRICAL PORTION THEREOF, AN OPERATING FLAT MEMBER CARRED BY SAID SHAFT AND SHAPED FOR ENGAGING AT LEAST ONE OF SAID FLUTINGS IN A POSITION SPACED FROM THE AXIS OF SAID MECHANICAL MEMBER, MEANS FOR 